[HWYSTR455]

My understanding is that the 'bypass' is actually the bleed, the stat is the highest part of the system, trapped air will naturally attract to that area. When the stat opens, trapped air moves to the rad, and the cap after X psi will 'burp' the rad.

The sleeves have the rubber rings on them because that is the pressure side of the pump. I see many confused about the direction of flow of the block holes. The water flows out the stat, or when the stat is closed, circulates in the block/heads/core/pump areas.

Intake to cover gaskets leak for a couple possible reasons:

* Shrinkage/dry rot of rubber ring
* Cover pitting where seal rides
* Incorrect installation/tightening sequence of intake bolts
* Use of incorrect bolt retainer/bolt length, bolt bottoming out

Causes when aftermarket intakes are used:

* Incorrect installation/tightening sequence of intake bolts
* Intake to head bolt holes not large enough to allow intake to be pulled forward enough to seal
* Intake seal area 'ridge' is too high, not allowing rubber ring to compress enough
* Cover pitting where seal rides
* Use of incorrect bolt retainer/bolt length, bolt bottoming out

I may have missed some, I'm still on first cup of joe, but that's what comes to mind at the moment.

I can't think of any good reason to block the bleed hole.

The only reason I can think of to drill holes in a stat is to maybe have more flow at a lower temp. Like you want to run a 180 stat, but also would like lower temps before the stat is FULLY open.

Cutting the crossover away from the intake runners is usually done to align intake/head ports, but also allows for easier intake swaps without breaking into the cooling system, like when testing intakes.

Personally, those 'high flow' stats do not work as well for me, and I generally see slightly higher temps across the board with them.



.